It is known in integrated circuits to realize specific functions with the aid of so-called switched capacitors (SC), for instance the function of an ohmic resistor. As is known, the impedance of a capacitor is calculated fiom the reciprocal value of the product of frequency and capacitance. Accordingly, for simulating ohmic resistors, integrated capacitors are controlled via switches, so that a continuous reloading operation takes place at the capacitor. The frequency of the control signal is matched to the capacitance of the capacitor such that the desired impedance is obtained.
By simulating ohmic resistors with the aid of switched capacitors, considerable chip area savings can be achieved.
For switching a "switched capacitor", an insulated gate field effect transistor (IGFET) is usually employed, and in particular two complementary field effect transistors (CMOS field effect transistors) connected in parallel to each other are employed.